Sadie was born at 8:35 a.m. on December 17, weighing 7 pounds, 6 ounces and measuring 19 inches long. A post on Grant's official website said that Mom and Sadie are both doing well.

"Perfect, healthy and GORGEOUS!" Grant tweeted about her new baby girl Friday morning.

Sadie Rose joins older twin sisters Isabella and Grace, who were born in early 2007.

Mom won't be following Sadie's arrival with too long of a break -- she has a busy load of tour dates already scheduled in 2011, including a spring tour with Nashville native Brandon Heath and contemporary Christian rock mainstays MercyMe.